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<br />seeding opportunities, assessed as such, would have occurred when inver- <br /> <br />s ions were present. <br /> <br />It IS or interest to note that of the 12 separate seeding periods <br />during the two month interval all but 2 were initiated between the <br />hours of D800 and 1700 }ISI; the others were initiated at 2100 and 2200 <br />HST. Yet in 8 of the seeding periods, seeding was carried en throughout <br />the night. These data indicate the practical limitations arising from <br />factors relating to the normal pattern of servicing by the generator <br />operators as well as the high fre~uency of inversions. <br /> <br />2.1.3 Airflow. Of the 12 periods of seeding 1:1 the two month <br />interval, 8 were accompanied by a westerly component of flow at 700 mb. <br />The remaining four were accompanied by easterly flow, at least during a <br />substantial fraction of the time. In the easterly flow cases seeding the <br />Tushars was accomplished by generators on the eastern side of the barrier <br />rather than the western side. <br /> <br />Ground based wind observations are also utilized in the analysis. <br />Cant inuous wind measurements recorded at the Adamsvi lIE: si te are sum- <br />marized in Table 3 for the periods of actual seeding. This selection <br />of data is made so that the diurnal variation of wind speed may be <br />found during cloudy condi t ions, part icularly when seeding is believed <br />appropriate. <br /> <br />Average speeds derived from the table clearly indicate a diurnal <br />variation, with weak nocturnal flow followed by an increase after 1000 <br />MST reaching a maximum around 1500 MST and a decrease thereafter to the <br />nocturnal value by 2000 ~ST. The nocturnal flow exists for an average of <br />about 14 hours. These data add confirmatory evidence for the typical <br />existence of inversions throughout the nighttime even in the presence of <br />generally cloudy conditions. <br /> <br />2.1.4 Ice nuclei observations at surface near mountain crest. <br />---- ------- ------ ----- -- - ------. - --- --- ---~------------ - --------------- <br /> <br />Observations of ice nuclei released from various generators in the <br />vicinity of the Tushar }1ouatains were made daily at ~1t. Holly (Holly <br />Station). Data for February, 1981 were invalidated due to an electronic <br /> <br />18 <br />